Protected electrical connector

ABSTRACT

An apparatus and method for protection of electrical contacts as well as a process for splicing electrical wires that are to be exposed to an adverse environment. The protection apparatus ensures that the electrical contacts are protected when they are otherwise located in an adverse environment. In a particular embodiment, the apparatus includes a connector, an insulating sleeve adapted to retain the connector, and an encapsulant. The encapsulant, which is disposed with protection apparatus, e.g. the insulating sleeve, has a cone penetration value of 100 to 350 (10 -1  mm) and an ultimate elongation of at least 200% and preferably an elastic modulus of less than 10 7  dynes/cm 2 .

This application is a continuation of U.S. Pat. No. 07/396,575 filedAug. 21, 1989 now U.S. Pat. No. 5,140,746, which is a continuation ofU.S. Ser. No. 07/183,546, filed Apr. 18, 1988, now U.S. Pat. No.4,864,725, which is a continuation of U.S. Ser. No. 07/038,415 filedApr. 9, 1987, now abandoned which is a continuation of U.S. Ser. No.06/756,559 filed Jul. 17, 1985, now abandoned which is a continuation ofU.S. Ser. No. 06/507,433 filed Jun. 23, 1983, now abandoned which is acontinuation-in-part of U.S. Ser. No. 06/504,000 filed Jun. 13, 1983,now U.S. Pat. No. 4,634,207 which is a continuation-in-part of U.S. Ser.No. 06/434,011 filed Oct. 12, 1982, now U.S. Pat. No. 4,600,261. Thedisclosures of Ser. No. 06/434,011 and 06/504,000 are incorporated byreference herein.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to electrical contacts and moreparticularly to apparatus and methods for protection of such electricalcontacts within an adverse environment. A particular embodiment relatesto electrical connectors in which connection between electrical wires iseffected by mechanical deformation of the connector.

Background of the Invention

For the purposes of the instant application, an electrical contactrefers to an electro-mechanical device that may be employed when it isdesired to readily connect (or disconnect) a first-insulated conductorto (or from) a second insulated conductor. Such a device is included,for example, in a conventional telephone circuit wire connector or in aconventional telephone electrical termination block of the type thatprovides telephone service to a customer.

A wide variety of substrates require protection from adverseenvironmental conditions, including moisture, insects, dirt, plant lifeand corrosion deposits. In some cases, especially when electricalcontacts are to be protected, it is desirable to provide a removableprotective cover over the substrate, so that it is possible easily toreenter and work on the sealed substrate. It is known to use greases toprotect electrical contacts, the grease being contained in a containerwhich is applied to the electrical contact(s)-see for example U.S. Pat.No. 3,897,129 (Farrar). However, the grease is a thixotropic fluid,which places limitations on the ways in which it can be used.Furthermore, when reentry to the sealed contact is required, when thecontainer is removed, grease remains coated on the contact(s) and mustbe cleaned off before electrical work can begin. It is also known toencapsulate electrical contacts within a container be means of atwo-part liquid composition prepared by mixing ingredients which willreact slowly together. Before the ingredients have gelled, the mixtureis poured into the container, where it cures in situ to form a hardgel-see U.S. Pat. Nos. 4,375,521 (Arnold) and 4,102,716 (Graves).However, this procedure involves preparation of the liquid compositionat the site, delay while the composition gels, and the need to provide acontainer around the contact(s), into which the composition can bepoured. Furthermore, when reentry to the encapsulated contacts isrequired, the gelled composition cannot easily be removed.

In order to explain how an electrical contact is included in a telephoneelectrical termination block, attention is directed to FIG. 1 whichshows a typical termination block 10. The termination block 10 includesa plurality of binding posts 12 which are, in fact, the electricalcontacts. The binding posts 12 each comprise a small screw-type contactthat facilitates the connection or disconnection of the first and secondinsulated conductors. Here, the first conductor may comprise a drop orservice wire 14 that is wrapped around the screw-type contact so as toprovide a connection between the customer and the termination block 10.The second conductor, on the other hand, may comprise a cable stub 16,which is pre-wired to a hermetically sealed portion of the terminationblock 10.

Although an end lead of the cable stub 16 is hermetically sealed withina portion of the termination block 10, the binding posts 12 (whichconnect one end of the service wire 14) may be exposed to the outsideenvironment. The binding posts 12 are typically kept in this exposedcondition in order to facilitate a craftsperson's reentry to thetermination block 10 in order to effect repairs or change a serviceconnection.

If the binding posts 12 remain exposed but unprotected from the outsideenvironment, they may be affected by environmental agents includingdirt, plant life, moisture, corrosion deposits and insects. Theseagents, however, can be adversative to the termination block 10 becausethey may effect a conductive bridge between some or all of the bindingpost contacts. This conductive bridge, in turn, may provide a means forthe creation of noise and may produce an electrical short-circuit withinthe termination block. It is noted in particular, that such terminationblocks that are left unprotected within humid or moist environments canincur a critical loss of insulation resistance between binding postcontacts which can result in a temporary or permanent disruption oftermination block operation or customer service.

In order to avoid disruption of service, therefore, it is important thatthe termination block be maintained so that it is resistant to the citedadverse environmental agents and can remain moisture insensitive.Consequently, it is important that the binding posts contacts (orelectrical contacts) be provided with a protection means (of the typeindicated generally by numeral 18 in FIG. 1) that insures there reliableand safe operation within an otherwise adverse and moisture-ladenenvironment.

In order to select an appropriate protection means for electricalcontacts, it is advantageous to realize the following design objectives.Thus, the protection means should not obstruct or delay a craftsperson'saccess to the reentrable electrical contacts. At the same time, and asits name suggests, the protection means should protect the electricalcontacts from the above described adverse environmental agents,including a high humidity environment. To these design objective ends,it is advantageous that the protection means utilize materials that arenon-hazardous, possess acceptable electrical properties including adesired insulation resistance and remain substantially inert toward amolded plastic substrate which typically houses the electrical contacts.

Embodiments of the present invention fulfill this need and satisfy thedesign objectives by providing a unique apparatus and method forprotection of electrical contacts. The apparatus of the presentinvention does not obstruct or delay a craftsperson's repeated reentrysto the electrical contact. At the same time, the present inventionsafely protects the electrical contacts even when they are exposed to anadverse environment. The present invention may consequently be employedwith a variety of electro-mechanical devices like connectors ortermination blocks where it is important to have ready access to thedevice while insuring, nevertheless, that the device is protected fromthe adverse environment.

It is also well known to splice (i.e. connect) electrical wires byplacing them within a connector and then permanently deforming theconnector by mechanical pressure-see for example U.S. Pat. No. 4,208,788to Siden. If the electrical wires so spliced are to be used in acorrosive, moist or hazardous environment, it is desirable to provide anenvironmental seal in association with the pressure connector in orderto maintain an acceptable electrical connection between the electricalwires.

Such environmental seals are known and include, for example, a specialbox which is designed to house the wire splice. In practice, however,the special box does not provide a hermetic seal; ultimately, moistureand/or other foreign substances may permeate the special box and inducecorrosion within the wire splice.

Other known environmental seals include a method of covering the splicedwires with a silicone grease. The silicone grease, however, isunsatisfactory since it can coat apparatus that should remain clean, andis displaced by vibration.

Environmental seals further include a crimp splicer wherein there is anassociated insulating heat shrinkable sleeve which is adapted to retaina crimp barrel therein. In practice, the heat shrinkable sleeve may beshrunk down around the barrel and electrical wires in order to protectthe splice from the environment. In some cases, however it isdisadvantageous or even prohibited, to employ a heating unit toheatshrink the sleeve.

Summary of the Invention

Accordingly, it is an object of the present invention to provide aprotection apparatus for electrical contacts.

It is a feature of the present invention that it enable a craftspersonto make numberable reentrys to the electrical contacts while ensuringthat the electrical contacts are protected when they are otherwiselocated in an adverse environment.

It is an advantage of the present invention that it may be employed withelectro-mechanical devices like termination blocks that includeelectrical contacts.

In accordance with the present invention, there is provided a protectionapparatus for an electrical contact. The apparatus includes aninsulating gel that is characterized by a cone penetration value frownapproximately 150 to 350 (10⁻¹ mm); an ultimate elongation of at leastapproximately 200%; a maximum tensile strength of approximately 20 psi;and a cohesive strength greater than its adhesive strength. Theapparatus further includes a first means to contain the gel, a secondmeans to retain the gel within the first means and a force means whichacts on the first means so that the gel is maintained in compressivecontact with the electrical contact and substantially encapsulates aconductive portion of the electrical contact.

I have now discovered that excellent encapsulation of electricalcontacts (and other substrates) can be obtained through the use of gelswhich have been preformed in the absence of the substrate (and likecompositions); the pre-formed gel and the substrate to be encapsulatedare pressed against each other, thus deforming the gel into close andconforming contact with the substrate. Preferably, at least a part ofthe deformation is elastic deformation. The preferred properties of thegel depend upon the substrate to be encapsulated, as further discussedbelow, but I have found that in all cases, it is essential for the gelto be relatively soft by comparison with the gels formed in situ in theknown processes. Thus the gels formed in in situ have cone penetrationvalues of less than 75, whereas the novel encapsulants of this inventionhave cone penetration values of at least 100. Cone penetration valuesgive in this specification are expressed in units of 10⁻¹ ram and aremeasured by ASTM D217-68 at 70° F. ±5° F., on an undisturbed sampleusing a standard 1:1 scale cone (cone weight 102.5 g. shaft weight 47.5g), the penetration being measured after 5 seconds. In addition, thenovel encapsulants should have an elongation of at least 200%.Elongation values given in this specification ace ultimate elongationsmeasured by ASTM D638-80 at 70° F. ±5° F., using a Type 4 die to cut thesample and at a speed of 50 cm/minute.

The novel encapsulant can be adherent to any suitable support member.Especially when it is desirable that the encapsulant should be removablefrom the electrical contact or other substrate which it is protecting,the encapsulant preferably has an adhesive strength to the substratewhich is less than its adhesive strength to the support member and lessthan its cohesive strength, so that the encapsulant can be cleanlyremoved front the substrate merely by separating the support member andthe substrate, leaving little or none of the encapuslant on thesubstrate. When the encapsulation of the substrate involves pushing atleast part of the substrate through the encapsulant so that theencapsulant is parted and then flows back to form a seal on the otherside of the substrate, the seal is a plane of weakness which will inmany cases separate cleanly when the encapsulant is removed. This is incontrast to the situation when an encapsulant is gelled in situ, when nosuch plane of weakness exists.

In one aspect, the present invention provides an apparatus for providinga protective covering over a substrate, the apparatus comprising asupport member and an encapsulant, the encapsulant being adherent to thesupport member and being composed of a material which has a conepenetration value of 100 to 350 and an ultimate elongation of at least200%.

In another aspect, the invention provides a process for providing aprotective covering over a substrate, which process comprises pressingtogether the substrate and an apparatus as define above, the apparatusand the substrate being pressed together so that the encapsulant contactthe substrate and is deformed into close and conforming contacttherewith.

I have now also discovered an in, proved electrical pressure connector,which protects the electrical wires from a corrosive, moist or hazardousenvironment. The apparatus of the present invention is easy andconvenient to employ and dispenses with a need for grease or a heatunit.

In one aspect, the present invention provides a connector, an insulatingsleeve adapted to retain the connector, and an encapsulant disposedwithin the insulating sleeve and/or the connector, the encapsulanthaving a cone penetration value of 150 to 350 and an ultimate elongationof at least 200%.

In another aspect, the present invention provides a process of splicingelectrical wires, comprising the steps of:

(a) inserting end sections of a at least two electrical wires into anapparatus that comprises:

(i) an electrical connector,

(ii) a deformable insulating sleeve that surrounds and retains saidelectrical connector; and

(iii) an encapsulant disposed within said insulating sleeve, saidencapsulant having a cone penetration value of 100 to 350 (10⁻¹ mm) andan ultimate elongation of a least 200%; and

(b) exerting pressure on said electrical connector through saidinsulating sleeve, thereby permanently deforming the connector toelectrically connect said electrical wires and encapsulate theelectrical connection with the encapsulant.

The end sections of the wires can be stripped of insulation before beinginserted into the connector, which, when it is crimped, mechanicallydeforms the end sections so that they are in physical as well aselectrical contact. Alternatively the insulation can be left on thewires, in which case the connector mus comprise an insulation displacingmember which, when the connector is crimped, displaces insulation on theend sections and effects electrical connection between the wires.

BRIEF DESCRIPTION OF THE DRAWING(S)

These and other features of the present invention will be more clearlyunderstood from a consideration of the following description taken inconnection with the accompanying drawings in which:

FIG. 1 provides a perspective view of a conventional telephoneelectrical termination block.

FIG. 2 provides an exploded view of one embodiment of a protectionapparatus made in accordance with the principles of the presentinvention.

FIGS. 3a and b show alternative embodiments of the present invention.

FIG. 4 is a cross-sectional view of an alternative embodiment of thepresent invention; and

FIG. 5 is a cross-sectional view of still another embodiment of thepresent invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference is now made to FIG. 2 which provides an exploded view of oneembodiment of a protection apparatus 220 made in accordance with theprinciples of the present invention. As shown in FIG. 2, the apparatus220 includes these component elements: an insulating gel 222 (whosefurther particular characteristics are set forth below); a first means224 to contain the gel 222 (here shown as a partitioned housing); asecond means 226 to retain the gel within the first means 224 (i.e. thehousing); and a force means 228 (shown symbolically in FIG. 2 as forcevectors). The force means 228 acts on the first means 224 so that thegel 222 is maintained in compressive contact with an electrical contact230 that is located on a support substrate 232 of a conventionaltermination block 234. At the same time, the force means 228 acts on thefirst means 224 so that the gel 222 substantially encapsulates aconductive portion 236 of the electrical contact 230.

The protection apparatus 220 shown in FIG. 2 has the following uniquefeature: if there is a release of the force means 228 and adisengagement of the first means 224 from the termination block 234, thegel 222 remains substantially with the first means 224 (i.e. thepartitioned housing). The gel 222, moreover, is cleanly as well asimmediately removed from the electrical contact 230. This unique featureenables the craftperson's to reenter the termination block 234 numerabletimes to effect repairs or change service wires connected to theelectrical contact 230. In all such cases of reentry, the gel 222remains substantially in the partitioned housing so that the craftpersoncan make repairs without obstruction or delay. After any repair is made,the craftsperson insures that the electrical contact 230 isenvironmentally protected by a method that includes the steps of:

1. providing an insulating gel 222;

2. providing a first means 224 of containing the gel 222;

3. providing a second means 226 for retaining the gel 222 within thefirst means 224; and

4. applying a force means 228 for acting on the first means 224 so thatthe gel 222 is maintained in compressive contact with the electricalcontact 230 and substantially encapsulates the conductive portion 236 ofthe electrical contact 230.

There is now provided, in sequence, a more detailed description of thecomponent elements set forth above for the protection apparatus 220 ofthe present invention.

The insulating gel 222 is particularly characterized by the followingincluded features: (1) a cone penetration value from approximately 150to 350 (10⁻¹ mm); an ultimate elongation of a least approximately 200%;a maximum tensile strength of approximately 20 psi; and a cohesivestrength greater than its adhesive strength. (Note that the statedparameters are provided in accordance with the American NationalStandard designation ASTM D217 and ASTM D638 for the cone penetrationand elongation parameters, respectively.)

The insulating gel 222 characterized by these stated features isprepared by extending a conventional aliphatic polyurethane compositionwith an admixture of mineral oil and vegetable oil from approximately 70to 80%; the ratio of mineral oil to vegetable oil being approximately0.7 to 2.4. Such an insulating gel 222 is tacky and is hydrolyticallystable, moisture insensitive and substantially inert towards the supportsubstrate 232. Additionally, the gel 222 is electrically insulating asit has a volume resistivity of at least approximately 109 ohmscentimeter. The gel 222 may also be provided with catalyst and otherknown additives such as moisture scavenger (e.g. benzoyl chloride),antioxidants, pigments and fungicides, etc. (all well known in the art).Other specific compositions for an insulating gel are conceivable andmay be employed within the scope of the present invention. For example,the composition can be realized as a nontacky gel.

As described above, the protection apparatus 220 includes the firstmeans 224 to contain the gel 222. In FIG. 2, the first means 224 isrealized by a partitioned housing. The partitioned housing includes sidewalls 238, end walls 240, a bottom wall 242 and a plurality ofpartitions 244. In this embodiment, each partition included within theplurality of partitions 244 encapsulates an electrical contact 230. Thepartitioned housing may be composed of a plastic material.

The first means 224 may also be realized by a non-partitioned housing or"open-through" type design (not shown). Other specific embodiments forthe design and type of material to be employed in the realization of thefirst means 224 are conceivable and may be made within the scope of thepresent invention as heretofore described.

It is also indicated above that the protection apparatus 220 includesthe second means 226 to retain the gel 222 within the first means 224(i.e. the partitioned housing). In general, the second means 226 toretain the gel 222 may include means to provide a surface area of thefirst means greater than a surface area of the electrical contact 230.To this end, the second means 226 may be realized by a conventionalsurface treatment process that includes abrasion of the surface wallareas of the partitions or the inclusion of material protrusions (notshown) within the included partitions. The second means 226 to retainthe gel 222 further includes chemical surface activation procedures suchas a corona treatment or a chemical treatment to enhance adhesion of thegel 222 to the first means 224.

Finally, it is indicated above that the protection apparatus 220includes the force means 228, shown symbolically as force vectors inFIG. 2. In one embodiment of the present invention, the force means 228is realized as a conventional nut and bolt assembly 246 which acts toinsure that the gel 222 is maintained in compressive contact with theelectrical contact 230 and that the gel 222 substantially encapsulatesthe conductive portion 236 of the electrical contact 230. Optimalresults are secured if the force means 228 (e.g. the nut and boltassembly) operates as a directional force that acts along an axisdefined by the electrical contact 230. Other specific embodiments (notshown) that realize the force means 228 include conventional tie wraps,string or bailing wire assemblies. It is noted, moreover, that the forcemeans 228 may be realized by a force that is substantially non-varyingin time or is dynamic.

The encapsulants used in the present invention have cone penetrationvalues of 100 to 350, with values of 150 to 350, especially 200 to 300,being preferred for processes in which the pressure exerted on theencapuslant during installation is relatively low, as for example in theencapsulation of electrical terminals as described in connection withthe drawing. When the volume of the encapsulant (or each mass ofencapsulant) is relatively large (e.g. more than 3 cc), the conepenetration value of the encapsulant is preferably 200 to 250. When thevolume is relatively small (e.g. less than 3 cc), the cone penetrationvalue is preferably 250 to 350.

The elongation of the encapsulant is at least 200%, and substantiallyhigher values are preferred, e.g. at least 500%, particularly at least750%. The tensile strength of the encapsulant is generally less, oftenvery much less, than 20 psi (measured by ASTM D638-80 under the sameconditions as the elongation).

The elastic modulus of the encapsulant is also significant, since itaffects the ability of the encapsulant to make intimate contact with thesubstrate. When measured at 70° F. ±5° F., using a parallel platerheometric test at a frequency of 1 Hz, the encapsulant generally has anelastic modulus less than 10⁷ dynes/cm², preferably less than 106dynes/cm², particularly less than 10⁵ dynes/cm².

Suitable materials for the encapsulant (which is usually electricallyinsulating, but is not necessarily so for some possible uses of theinvention e.g. when non-electrical substrates are being protected) canbe made by gelling curable polyurethane precursor materials (asdescribed for example in the patents referenced above) in the presenceof substantial quantities of a mineral oil, a vegetable oil or aplasticizer, or a mixture of two or more of these. Thus I have obtainedexcellent results using encapsulants prepared by gelling componentswhich are commercially available for the preparation of polyurethanegels in situ, the gelation being carried out, however, in the presenceof a suitable amount e.g. 30 to 70% by weight, of a suitableplasticizer, e.g. a trimellitate, or in the presence of a suitableanimal or vegetable oil e.g. 80 to 60%, preferably 80 to 70%, by weightof a mixture of mineral and vegetable oils in which the ratio by weightof mineral oil to vegetable oil is 0.7 to 2.4. Other suitableencapsulants can be prepared by curing reactive silicones withnon-reactive extender silicones.

A wide variety of support members are useful in the present invention.In some cases a conventional rectangular container, having side walls,end walls and a bottom wall, is satisfactory. When a plurality ofadjacent contacts are to be encapsulated, it is often useful for thesupport member to comprise a plurality of individual open containers,which are connected to each other, e.g. through a flexible connectionmeans, and each of which contains a separate mass of encapsulant. Theseparate containers can be applied simultaneously or sequentially to thecontacts. The support member can be of any material, but preferably itis composed of an organic polymer or some other insulator. The supportmember can be recoverable, preferably heat-recoverable, in which casethe process for applying the protective covering to the substrateincludes a step in which the support member is recovered. When using arecoverable substrate, the elastic modulus of the encapsulant isparticularly important, but the elongation can be substantially, lessthan 200%, e.g. as little as 50%, though preferably at least 100%

Especially when at least part of the deformation of the encapsulant iselastic deformation, it is often necessary to provide a force member formaintaining the encapsulant in compressive contact with the substrate.The force member is preferably secured to or forms part of the supportmember, but can be separate from it. The force member can be such thatit becomes secured to the substrate when the substrate and theprotective apparatus are pressed together. For example the force membercan lie within the encapsulant and engage the substrate to which theencapsulant is applied. In the embodiment of the present invention asshown in FIG. 2, the force means 228 is considered to be an independentelement which acts on a concentrated load (i.e. the first means 224 thatcontains the encapsulant). The force developed by the force means 228 iseffectively transmitted and distributed by way of the first means 224 sothat the encapsulant 222 maybe in compressive contact with each of aplurality of electrical contacts 236.

This alternative embodiment of the present invention is shown in one ofits aspects in FIG. 3a and includes a means 338 to contain and retainthe encapsulant 312 and to develop a force to maintain the encapsulant312 in compressive contact with the electrical contact 320 and thesupport substrate 322. The means 338 is realized by way of a structurethat includes a housing that has a generally bell shaped configuration.Thus, the housing has a narrow necked portion that opens up at one endso as to be able to fit over the electrical contact 320. Integral to thehousing is a split retaining nut member 340 that has an internalthreaded portion that is complementary with the threads of theelectrical contact 320. The member 340 is split so that it may be pushedaxially onto the electrical contact 320, without threading it duringthis pushing action. On the other hand, the member 340 is internallythreaded so that it can grip the electrical contact 320 upon thecessation of the pushing action, thus realizing the force that maintainsthe encapsulant 312 in compressive contact with the electrical contact320 and the support substrate 322.

In sum, the alternative embodiment of the present invention shown inFIG. 3a includes the means 338 which (1) contains the encapsulant 312;(2) retains the encapsulant 312 (in the manner established above); and(3) develops a force to maintain the encapsulant 312 in compressivecontact with the electrical contact 320 and the support substrate 322.The means 338, as shown by way of FIG. 3a embodiment, may be realized bya conventional polymeric or elastomeric material. A plurality of themeans 338 elements, moreover, may be connected together by way of aconnecting ribbon 342. The ribbon 342 facilitates the job of thecraftsperson, wherein an array of electrical contacts 320 are servicedas a group, and re-entry is effected simply by pulling the ribbon 342away from the termination block 324. To the same end, note anotherembodiment of the presentinvention, shown in FIG. 3b, wherein the means338 is realized by a uniblock device 344 that is molded to fit over theentire termination block 324.

The present invention, as heretofore disclosed, provides apparatus andmethod for protection of electrical contacts. The principles of thepresent invention, however, are more general and extend to apparatus andmethod for providing a protective covering over any substrate e.g. thesupport substrate 322. The generalized apparatus and method of thepresent invention is now disclosed.

As generalized, also a method of the present invention includes aprocess for providing a protective covering over a substrate, andcomprises the steps of:

(a) pressing together the substrate and a protective member comprising asupport member and an encapsulant which is adherent to the supportmember. The encapsulant preferably has cone penetration value of 150 to350 (10⁻¹ mm) and an ultimate elongation of at least 200% and anadhesive strength to the substrate which is less than its adhesivestrength to the support member and less than its cohesive strength. Theprotective member and the substrate are pressed together so that theencapsulant contracts the substrate and is deformed into close andconforming contact with the substrate; preferably at least a part of thedeformation is elastic deformation; and

(b) maintaining the encapsulant in contact with the substrate.

Still another embodiment of the invention is described herein mainly byreference to an in-line crimp splicer as shown in FIG. 4, but it is tobe understood that the invention extends to electrical pressureconnectors, generally, and therefore further encompasses e.g. pigtailconnectors (or wire joints). It is also noted that the invention may bepracticed when it is desired to connect two or more electrical wires.

Attention, accordingly, is directed to FIG. 4, which shows across-sectional view of a crimp splicer 410. The crimp splicer 410includes three elements; a connector 412, an insulating sleeve 414 andan encapsulant 416. These elements are now discussed in detail, but itis to be understood that the various features disclosed with referenceto FIG. 4 are also applicable, mutaris mutandis, to other pressureconnectors of the invention.

The connector 412 is preferably cylindrical or barrel shaped andconsists of a ductile metal which is a good conductor and is capable ofbeing deformed with a crimping device (not shown). Suitable metals arecopper, aluminum or brass. The connector 412 is also provided with acentrally located conductor stop 418 formed by perforating one side ofthe wall of the connector 412 and forcing a portion of the wall into theinterior of the connector 412.

The insulating sleeve 414 is generally cylindrically-shaped and has abore formed therein which runs the length of the sleeve. The sleeve 414is shaped and sized to enable mechanical retention of the connector 412disposed within the bore of the sleeve 414. Suitable materials for thesleeve 414 include nylon and polyvinylidene fluoride, since thenecessary crimping force can be applied through these materials, in anappropriate manner well known in the art, without damage to theinsulating sleeve or loss of retention of the connector 412.

The encapsulant 416 has a cone penetration value of 100 to 350 (10⁻¹mm), preferably 100 to 250. (Note that the cone penetration value isdetermined in accordance with the American National Standard DesignationASIM D217-68 on an undisturbed sample at 70° F. ±5° F. using a standard1:1 scale cone (cone weight 102.5 g, shaft weight 47.5 g), thepenetration being measured after 5 seconds. Further, the encapsulant 416has an ultimate elongation of a least 200%, especially at least 500%;and generally has a maximum tensile strength of approximately 20 psi.(Note that these parameters are determined in accordance with theAmerican National Standard Designation ASTM D638-80, at 70° F. ±5° F.,using a Type 4 die to cut the sample and at a speed of 50 cm/minute).

The encapsulant 416 may be prepared by gelling a liquid mixturecomprising suitable gel precursor materials, e.g. polyurethane orpolysiloxane precursor materials, together with suitable reactive ornonreactive extenders. For example, suitable encapsulants can be made bygelling a mixture comprising conventional curable polyurethane precursormaterials in the presence of substantial quantities of a mineral orvegetable oil or a mixture thereof (e.g. in amount 60 to 80%) or asuitable plasticizer, e.g. a trimellitate such as n-ocytl-n-decyltrimellitate (e.g. in amount 30 to 70%). A suitable reactive extenderfor polyurethane precursors is a mixture of mineral and vegetable oilsin which the ratio by weight of mineral oil to vegetable oil is 0.7 to2.4 the mixture of oils being present in amount 80 to 60%, preferably 80to 70% by weight based on the total weight of the polyurethane precursormaterials and the mixture of mineral and vegetable oils. The encapsulant416 may contain known additives such as moisture scavengers (e.g.benzoyl chloride), antioxidants, fillers, pigments, and fungicides.Especially when the wires are crimped into direct physical contact, theencapsulant can contain abrasive fillers which will pierce through anyoxide or other passivating layer on the conductors, particularlyaluminum conductors, especially in medium and high voltage joints. Otherspecific compositions for encapsulant 416 are conceivable and may beemployed within the scope of the present invention. For example, thecomposition may be prepared by curing reactive silicones dissolved innon-reactive extender silicones. The encapsulant 416 is electricallyinsulating and preferably has a volume resistivity of at least 109 ohmscentimeter. Additionally, the encapsulant 416 is hydrolytically stable,moisture insensitive, substantially inert towards the insulating sleeve414 and tacky.

Note that it is advantageous to dispose the encapsulant 416 within thesleeve 414 so that it substantially fills up the bore which runs thelength of the sleeve 414. In this manner, the electrical wires 420 and422 penetrate the encapuslant 416, which then seals behind the insertedwires 420 and 22. Moreover, the encapsulant 416 is voided from the areaof electrical contact by the mechanical pressure generated during thecrimping step (b) above. In this way, consequently, the presentinvention provides an electrical splice: the encapsulant 416 ensuresthat the splice protects the electrical wires 420 and 422 from acorrosive, moist or hazardous environment. In an alternative embodimentof the present invention, not shown, the sleeve 414 is provided withflexible end-guards which shield and protect the encapsulant 416 fromdust and incidental contact with solvents.

The apparatus of the present invention also extends to a "B-wire"connector 524 of the type shown in FIG. 5. Here, a connector 526 whichis covered with an insulated layer 528 is adapted to receive insulatedelectrical wires (numerals 530, 532). The apparatus comprises aninsulation displacing member which, when the connector 524 is crimpedaround insulated electrical wires placed within the connector, displacesinsulation on the electrical wires and effects electrical connectionbetween the wires.

The present invention, in summary, may be employed to provide aprotection apparatus for electrical contacts. Although specificembodiments of the present invention have been described herein, it willbe obvious to those skilled in the art that various modifications may bemade without departing from the spirit of this invention. With suchincluded modifications, the present invention is suitable for employmentwith a wide variety of devices including termination blocks, telephoneconnectors or conventional splice connectors. In all such cases ofemployment, a craftsperon can make numerous reentrys to the device whileensuring that the electrical contacts therein are protected when theyare otherwise located in an adverse environment. Additional embodimentsof the present invention in summary, may also be employed to maintain anacceptable electrical connection between spliced wires by encapsulatingand hence sealing the electrical connection from an adverse environment.Although specific embodiments of the present invention have beendescribed herein, it will be obvious to those skilled in the art thatvarious modifications may be made without departing from the spirit ofthe invention.

With the forgoing in mind, it is understood that the invention beaccorded the full scope of the appended claims.

What is claimed is:
 1. A device for protecting an electrical contact andwire connection, comprising:(1) a gel formed prior to making theconnection between the electrical contact and wire, said gel having anelastic modulus of less than 10⁶ dynes/cm², an ultimate elongation of atleast 200%, and is capable of undergoing elastic deformation around theelectrical contact and wire; (2) a container for the gel; and (3) aforce member adapted to cooperate with and act on said container to movethe container and gel from a first position to a second position wherebyupon connection of the electrical contact and wire said gel within thecontainer is elastically deformed and maintained in direct engagementwith said electrical contact and wire so that said electrical contactand wire connection is environmentally sealed.
 2. The device accordingto claim 1 wherein said gel is initially formed in contact with saidcontainer and said gel has a cone penetration of 150 to 350 (10⁻¹ mm).3. The device according to claim 2 wherein the elastic modulus of saidgel is less than 10⁵ dyne/cm².
 4. The device according to claim 3wherein said container includes an electrical contact and said gel, saidgel having an adhesive strength to the wire to be sealed which is lessthan the gel's cohesive strength.
 5. The device according to claim 1wherein said container houses an electrical contact and where said forcemember comprises in part a bolt member acting in combination with saidcontainer.
 6. The device according to claim 5 wherein said gel has acone penetration of 150 to 350 (10⁻¹ mm).
 7. The device according toclaim 6 wherein the electrical contact is an insulation displacementelectrical contact contained within said container.
 8. A device forprotecting an electrical contact and wire connection, comprising(1) agel formed prior to making the connection between the electrical contactand wire, said gel having an elastic modulus of less than 10⁶ dynes/cm²,and an ultimate elongation of at least 200%; (2) a container for thegel: and (3) a force member adapted to cooperate with and act on saidcontainer to move the container and gel or an electrical contactcontaining member from a first position to a second position such thatupon connection of the electrical contact and wire said gel within thecontainer is elastically deformed and maintained in direct engagementwith said electrical contact and wire so that said electrical contactand wire connection is environmentally sealed; said force member alsoadapted to move the container or an electrical contact containing memberfrom said second position to said first position whereby said electricalcontact and wire may be disconnected; and wherein said gel has acohesive strength greater than its adhesive strength whereby upondisconnection of the electrical contact and wire, said gel remainssubstantially within said container.
 9. The device according to claim 8wherein said gel a cone penetration of 150 to 350 (10⁻¹ mm).
 10. Thedevice according to claim 9 wherein said gel is initially formed incontact with said container and electrical contact.
 11. The deviceaccording to claim 10 wherein said force member is selected to include amember from the group consisting of a nut, a bolt, and combinationsthereof.
 12. The device according to claim 11 wherein said container iscomposed of an organic polymeric material and said gel is an aliphaticpolyurethane composition selected from the group consisting of aplasticized polyurethane, an oil-extended polyurethane.
 13. The deviceaccording to claim 10 wherein said gel is a silicone gel with an elasticmodulus less than 10⁵ dyne/cm².
 14. The device according to claim 8wherein said gel is selected from the group consisting of gelssubstantially inert towards the wire; hydrolytically stable moistureinsensitive and electrically insulating gels; tacky gels; non-tackygels; and gels with combinations of properties thereof.
 15. A device forprotecting an electrical contact and wire connection wherein the contactis mounted in a base and the wire is external to the base.comprising:(1) a gel formed prior to making the connection between theelectrical contact and wire. Said gel having an elastic modulus of lessthan 10⁶ dynes/cm ² and an ultimate elongation of at least 200%; (2) acontainer for the gel; and (3) a force member adapted to move thecontainer relative to said base between a first unsealed position topermit connection of the electrical contact and wire and a secondenvironmentally sealed position wherein said gel within the container iselastically deformed and maintained in direct engagement with saidelectrical contact and wire connection.
 16. The device according toclaim 15 wherein said gel having a cone penetration of 150-350 (10⁻¹mm).
 17. The device according to claim 16 wherein said gel is initiallyformed in contact with said container.
 18. The device according to claim15 said gel having a cone penetration value of 150-350 (10⁻¹ mm), saidgel having an adhesive strength to the wire to be sealed which is lessthan the gel's cohesive strength.
 19. The device according to claim 15wherein said container surrounds an electrical contact and said gel isinitially formed in contact with said container and electrical contactand said gel has a cone penetration value of 150-350 (10⁻¹ mm).
 20. Thedevice according to claim 15 wherein with said container is associatedwith an insulation displacement electrical contact and said gel, saidgel having an adhesive strength the wire to be sealed which is less thanthe gel's cohesive strength and an elastic modulus of less than 10⁵dynes/cm² and a cone penetration value of 150-350 (10⁻¹ mm), and saidforce member includes a bolt member.
 21. A reusable apparatus forenvironmentally protecting a wire and electrical contact connection,said apparatus comprising: a reusable receptacle for housing the wireand electrical contact connection:a gel formed prior to making the wireand electrical contact connection, said gel being disposed within saidreceptacle and having an ultimate elongation of at least 200%, anelastic modulus of less than 10⁶ dynes/cm², and a cone penetration of150-350 (10⁻¹ mm); a repeatedly activateable force member assembled withsaid receptacle to cause elastic deformation of said gel at said wireand electrical contact connection when said force member is activated toenvironmentally seal the connection.
 22. The reusable protectionapparatus of claim 21 wherein said force member acts to move saidreceptacle from a first position to a second position.
 23. The reusableprotection apparatus of claim 22 wherein said receptacle is completelyseparable from said electrical contact.
 24. The reusable protectionapparatus of claim 21 wherein said force member acts to move theelectrical contact from a first unsealed position to a second sealedposition.
 25. A reusable protection apparatus for environmentallyprotecting a plurality of wire and electrical contact connections saidapparatus comprising:a plurality of wire and electrical contactconnections; at least one reusable receptacle for isolating one of saidelectrical contact and wire connections; a gel formed prior to makingthe wire and electrical contact connection, said gel being disposedwithin said receptacle and having a cone penetration of about 150 toabout 350 (10⁻¹ mm) and an ultimate elongation of at least about 200%and an elastic modulus of less than 10⁶ dynes/cm² ; and a repeatedlyactivateable force member assembled with said receptacle to causecompression of said gel at said wire and electrical contact connectionwhen said force member is actuated whereby the sealing by the gel of thewire and electrical contact connection prevents shorting betweenadjacent electrical contact wire connections.